Detecting 'floppy' like umass devices

[Bernd Walter]

On Mon, Apr 19, 2004 at 10:47:48PM +0930, Daniel O'Connor wrote:
> A friend of mine handed me a USB flash key today that has 2 'partition' - one 
> 1.44Mb chunk pretends to be a floppy drive and the rest is a normal umass 
> device.
> 
> I am wondering if there is any way of telling if a given umass device is 
> a floppy drive (or wants to look like one) - eg I have a USB FDD which 
> I imagine should fall into the same basket.

What do do you mean with "wants to look like one".
In which way does a floppy look different from other direct access
drives?
They all read and store direct access data.

> I note that you get wacky values from fdisk when you try and read partition 
> table from them too..
> 
> On another note my USB floppy drive does 2k/sec in FreeBSD :(

Sound like another instance of msdosfs does no clustering and drive
is too stupid to get speed without.
IIRC there were some work on this point, but I don't now the state.
Check the speed with dd and different blocksizes.

> It's one of these ->
> Apr 19 22:45:32 inchoate kernel: umass0: NEC NEC USB UF000x, rev 1.10/1.50, addr 2
> Apr 19 22:45:33 inchoate kernel: (probe0:umass-sim0:0:0:0): INQUIRY. CDB: 12 0 0 0 24 0
> Apr 19 22:45:33 inchoate kernel: (probe0:umass-sim0:0:0:0): CAM Status: SCSI Status Error
> Apr 19 22:45:33 inchoate kernel: (probe0:umass-sim0:0:0:0): SCSI Status: Check Condition
> Apr 19 22:45:33 inchoate kernel: (probe0:umass-sim0:0:0:0): UNIT ATTENTION asc:29,0
> Apr 19 22:45:33 inchoate kernel: (probe0:umass-sim0:0:0:0): Power on, reset, or bus device reset occurred
> Apr 19 22:45:33 inchoate kernel: (probe0:umass-sim0:0:0:0): Retrying Command (per Sense Data)
> Apr 19 22:45:35 inchoate kernel: da0 at umass-sim0 bus 0 target 0 lun 0
> Apr 19 22:45:35 inchoate kernel: da0: <NEC USB UF000x 1.50> Removable Direct Access SCSI-0 device
> Apr 19 22:45:35 inchoate kernel: da0: 1.000MB/s transfers
> Apr 19 22:45:35 inchoate kernel: da0: 1MB (2880 512 byte sectors: 64H 32S/T 1C)
> Apr 19 22:45:36 inchoate kernel: umass0: Unsupported UFI command 0x35
> Apr 19 22:45:36 inchoate kernel: (da0:umass-sim0:0:0:0): Synchronize cache failed, status == 0x6, scsi status == 0x0
> Apr 19 22:45:36 inchoate kernel: umass0: Unsupported UFI command 0x35
> Apr 19 22:45:36 inchoate kernel: (da0:umass-sim0:0:0:0): Synchronize cache failed, status == 0x6, scsi status == 0x0

Nothing wrong with those messages.

> I have a Dell Inspiron 8600 with a
> uhci0: <Intel 82801DB (ICH4) USB controller USB-A> port 0xbf80-0xbf9f irq 11 at device 29.0 on pci0
> 
> I have tried a USB flash card reader which gets ~500k/sec.

If a drive doesn't preread blocks then each access has to wait for the
media - undoubly flash has a faster access time than floppies...

-- 
B.Walter                   BWCT                http://www.bwct.de
bernd at bwct.de                                  info at bwct.de